How are hints hidden from view?
Glyphs 2 will have an option in the View menu.
Btw, will this problem be solved soon?
http://www.glyphsapp.com/forums/index.php?action=vthread&forum=1&topic=2173
At the moment, manually hinting is practically possible only for those glyphs that are not used as a component anywhere in the font. Which makes the whole feature barely useful.